In general, a standard system update will make all the necessary changes.

Details follow:

Alexander Kurtz discovered that sudo would not prompt for a password when
a group was specified in the Runas_Spec. A local attacker could exploit
this to execute arbitrary code as the specified group if sudo was
configured to allow the attacker to use a program as this group. The group
Runas_Spec is not used in the default installation of Ubuntu.